This occurred with one of my team mates on his newly installed QTP 9.5. With QTP 9.2 and earlier, we use to run the QuickTest Professional.bat file present under QuickTest Professional/bin folder and it took care of the unregistered, corrupted DLL’s. In 9.5 there is no such .bat file present under bin folder.

The best way out now is to go to Add/Remove Programs > QuickTest Professional > Click on ‘Change’ (not ‘Remove’!) > Select the ‘Repair’ radio button.

When QTP hangs

Follow the instructions on the screen. Restart your system and most probably QTP will work now (at least that it how it worked for him!)